Tvrdi metali s alternativnim vezivima

master's thesis

• Title (english): Hard metals with alternative binders
• Author: Antonio Stepić
• Mentor: Željko Alar (mentor)
• Mentor: Tamara Aleksandrov Fabijanić (komentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2020-12-03, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Tvrdi metali s alternativnim vezivima područje su intenzivnog znanstvenog istraživanja. U gotovo stogodišnjoj povijesti tvrdih metala najčešće su primjenjivani WC-Co sustavi zbog zadovoljavajuće kombinacije mehaničkih svojstava. Uslijed visoke cijene kobalta, toksičnosti Co prašine te sve većih industrijskih zahtjeva počelo se pribjegavati istraživanju i primjeni tvrdih metala s alternativnim vezivima.
U radu su uvodno opisane osnove o metalurgiji praha te povijest, kemijski sastav, mikrostruktura i svojstva tvrdih metala. Pojašnjeni su razlozi istraživanja alternativnih veziva, detaljno je opisan pregled različitih vrsta alternativnih veziva prema trenutno dostupnim znanstvenim radovima te su prikazani primjeri primjene tvrdih metala s alternativnim vezivima. U eksperimentalnom dijelu rada ispitani su mikrostruktura, mehanička svojstva te korozijska postojanost WC-11Ni i WC-11Co uzoraka tvrdih metala.
Rezultati ispitivanja potvrdili su superiorna mehanička svojstva konvencionalnog tvrdog metala. Međutim, ispitani tvrdi metal s alternativnim vezivom posjeduje bolju korozijsku postojanost što mu omogućuje određene industrijske primjene.

Abstract (english)

Hard metals with alternative binders are an area of intensive scientific research. In the almost hundred-year history of hard metals, WC-Co systems have been the most widely used due to the satisfactory combination of their mechanical properties. Due to the high price of cobalt, the toxicity of Co dust and the growing industrial requirements, research and application of hard metals with alternative binders have been more and more investigated.
The introductory part of the paper describes the basics of powder metallurgy and the history, chemical composition, microstructure and properties of hard metals. The reasons for the research of alternative binders are explained, an overview of different types of alternative binders according to currently available scientific literature is described in detail, and examples of the application of hard metals with alternative binders are presented. In the experimental part of the paper, the microstructure, mechanical properties, and corrosion resistance of WC-11Ni and WC-11Co samples of hard metals are examined.
The experimental results confirmed the superior mechanical properties of conventional hard metal. However, the tested hard metal with an alternative binder possesses better corrosion resistance which makes it suitable for certain industrial applications.

• Keywords: metalurgija praha; tvrdi metali; alternativna veziva; kobalt; nikal; mikrostruktura; mehanička svojstva; korozijska postojanost
• Keywords (english): powder metallurgy; hard metals; alternative binders; cobalt; nickel; microstructure; mechanical properties; corrosion resistance
• Language: croatian
• URN:NBN: urn:nbn:hr:235:045823
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-11-25 11:41:44